Microscope Workplace Design in Quality Control

Sensor and identification technology, industrial cameras: when top precision is required, the name Baumer Electric is soon mentioned. The Swiss company designs and produces components for manufacturing facilities all over the world. To be able to guarantee that the finished components are of the highest possible quality, elaborate quality inspections are carried out part for part under the stereo microscope. At he company’s main plant in Frauenfeld, Switzerland, Baumer demostrates how workplaces have to be designed to enable quality control staff to stay fully concentrated for eight hours.

Despite all the blessings of automation: the management of Baumer Electric insists on final control of all the assemblies and components the company makes. Around 30 women are employed in the quality control department to carefully inspect the IPC-conformity of the assemblies. Have all the soldered joints been done accurately, is the polarity of all the fitted parts correct? Some of the things that have to be checked can be seen with the naked eye. But most parts of the inspection have to be done under the microscope.

Authors

Topics & Tags

Table of Content

Microscopy is extremely hard work

Microscopy makes tough demands on eyesight as well as the fine motor and skeletal system. The most common health problems at microscope workplaces are head, neck and back pain, stiff shoulders and symptoms of eye strain. To enable the quality control team to maintain the high level of concentration required for their job over the whole day, considerable attention is paid to the ergonomic design of their workplaces. Everything that has a detrimental effect on their body, eyes and organism has to be eliminated or at least reduced to a minimum.

First: the right furniture

Workplace design – ergonomics in a broader sense embraces equipment, workstations, working environment and work content – begins with height-adjustable desks and chairs. A specially trained member of staff helps the visual inspection team adjust the furniture to the anatomically correct sitting position, adding a footrest if necessary. As goods control is a single-shift operation at Baumer, all the staff have a fixed workplace individually adjusted to their needs. Whereas equipping workplaces with ergonomically correct furniture is meanwhile standard practice served by a wide range of suitable products on the market, choosing the stereo microscopes is a challenge.

Choosing microscopes

Putting it simply, there are three main technical factors to bear in mind when looking for the perfect ergonomic microscope. The first one is the build of the microscope, which influences posture and handling. Secondly, the design of the illumination has to ensure fatigue-free viewing. The third point concerns the optics system. Here, it’s details that make all the difference – a difference users may not notice until they have been working with the microscope for a long time.

Baumer Electric was already using the stereo microscope Leica MZ6, which fulfills all the criteria for fatigue-free working. After exploring the market, the quality control management decided to purchase the successor model, the Leica M60, last year. The new microscope offers a whole range of new features for making work easier and more pleasant.

Fig. 1: Manual assembly in the Electronics department.

Optimizing the microscope to suit the user

In constructional terms, the new microscope has basically retained the successfully proven shape of the predecessor model. One of the new features is the 6.3 : 1 zoom with seven click-stop settings that allow exact reproduction of the inspection conditions. The women greatly appreciate the precise position locking and say that getting the job done is now even easier. In ergonomics, it is technical details like these that foster satisfied, relaxed working conditions.

Leica Microsystems offers a variety of ergonomic modules for its stereo microscopes that ensure an optimal sitting position. The Leica ErgoWedge™ enables users to change the viewing position when using fixed-angle tubes. The Leica ErgoWedge™ is assembled between the zoom body and the binocular tube and allows the viewing angle to be changed when using already installed 45° binocular tubes. With modules like this, Baumer is able to adjust existing microscopes to the individual needs of new users. When employees complain of headaches, it is generally due to an unfavorable position of the eyepiece. This "problem zone" can be easily mitigated with an ergowedge retrofit.

Not every illumination solution is the same

Substantial innovations in lighting technology facilitate the quality control team’s work enormously. Visual checking of electronic components is always particularly challenging, as they constantly have to contend with reflections from metallic surfaces. The new compact Leica LED3000 RL ring light illumination brings a distinct improvement. Integrating newest-generation LEDs and a focusing lens specially designed by Leica Microsystems, it provides excellent homogeneity and brightness compared with conventional lighting concepts.

Fig. 2: Visual inspection by a manual assembly worker. The soldering and the polarity of the components are checked and corrected and missing components found.

Contrast and depth of field

A polarization set can be ordered as an accessory for the right light. Its polarizing filter minimizes light reflexes caused by metallic surfaces. The women report a significant reduction in glare when looking at the circuit boards. Besides the lack of disturbing reflections, they find the enhanced contrast easier on the eye and beneficial for detecting image details more quickly. The microscope’s excellent depth of field is also a popular feature, as the samples can be inspected without refocusing.

Looking ahead

Do they have any suggestions for improving the Leica MZ6? The women and the production manager came up with a few ideas which the editors passed on to the responsible product management. The greatest wish of the production manager goes in a completely different and new direction: he would like to have a digital microscope to go with the 30 stereo microscopes. This would allow shared on-screen viewing and discussion of components in comfort. It would also give them the possibility of recording images and films for long-distance communication or documentation. From an ergonomic point of view, he said, the digital microscope also had the advantage that screen viewing gave the staff more freedom of movement.

Baumer’s active commitment to ergonomics and the involvement of staff in work processes is corroborated by a recent nomination: the CRF Institute again voted Baumer Electric one of Switzerland’s "Top Employers" (www.topemployers.ch).

The Baumer Group employs more than 2,300 people in 37 subsidiaries and 19 countries all over the world. The Group is a global leader in the development and production of sensors, shaft encoders, measuring instruments and components for automated image processing. 12 % of the Frauenfeld workforce is employed in R&D, where hard- and software engineers, design and process engineers develop innovative sensors.

As one of the market leaders, the Frauenfeld company is continually raising the bar and investing in its technological lead. A large number of pioneering sensors have been launched on the market in recent years, paying particular attention to miniaturization, precision, measuring speed and robustness. These are the features that make Baumer sensors so special.